Research On Lightweight Glubam Frame Structures

Bamboo resources,which are fast-growing materials,are abundant in China and have a good industrialization foundation.Modern bamboo structures which take industrialized laminated bamboo panel products as raw materials,can be manufactured and assembled industrialized,and meet the corresponding safety,economic,comfortable,and related structural performance requirements.Therefore,this dissertation systematically studied the basic material properties,design of main structural components,BIM platform,and engineering applications of lightweight laminated bamboo(glubam)frame structure.The primary researches and achievements are summarized as follows:First,based on the ASTM and ISO standards of test methods for small clear specimens of timber,and the distribution of bamboo strip in glued l aminated bamboo panels,the experimental studies on basic mechanical properties of industrialized laminated bamboo panels with different thickness,including tension,compression,bending and shear strengths were conducted.The embedment strength of the laminated bamboo panel under the action of a dowel type fastener is an essential parameter for calculating the bearing capacity of the connection system and is a primary variable of the engineering design of the glubam structure.Thus,in accordance with international standards,tests of embedment strength of glubam for different fasteners and different loading directions were conducted,and the design formula of embedment strength was obtained by the maximum likelihood method.Based on the obtained test information of material properties with different test numbers,the characteristic and design values of basic mechanic properties were estimated through the Monti-Li simplified method and compared with the characteristic values determined by the Chinese code.The characteristic and design values of embedment strength under the action of different fasteners and different loading directions were estimated by the method given in Eurocode 0 Appendix D.The horizontal floor,shear wall,and roof system,which are the main structural components of lightweight glubam structure,are usually made with frame and sheathing panels connected by fasteners.The main components are also joined by metal connections.So the connection system is an essential factor influencing the performance of the whole structure.In this dissertation,the analytical models and calculation methods of bearing capacity of connection system were presented,meanwhile,based on the theoretical researches,the experimental studies of the connection system of the lightweight shear wall,which is the main component resisting lateral force,including panel-frame connection,frame-frame connection,and hold-down connection,were performed according to standards.Mechanical parameters are obtained,and the test results are com pared with theoretical ones.The design process of 1-2 story lightweight frame structure with limited vertical loads was summarized,and the calculation and analysis methods of the main structural members of light-frame structures-shear wall,floor diaphragm,and truss were summarized based on the design codes of different countries.The experimental studies on the lateral resistance of lightweight frame shear walls were carried out.Test results showed that the application of laminated bamboo panels in li ghtweight frame shear walls could improve the bearing capacity of the wall,but the deformability was reduced.The finite element models of lightweight shear walls based on test information of connection system s were established by SAP 2000,and the influence of different nail connectors,nail spacing,framing materials,etc.on the lateral resistance of shear walls were simulated and analyzed.The model can be used as a useful tool for design and performance estimation of lightweight shear walls.Based on the simulation results of shear walls,a 3D model was established by the Open Sees program to simulate the overall structural performance.At the same time,this type of laminated bamboo shear wall can be innovatively used in various structures as a structural-decorative integrated component.Finally,a brief introduction of lightweight glubam structures and innovative application of structural components that had been completed or in progress was given to validate structural feasibility and development poten tial.In accordance with the original drawing information of one lightweight glubam structure project in Purple Bamboo Park in Beijing,the building information model(BIM)was established with BIM software Autodesk Revit and wood structure design plug AGACAD.In this dissertation,exploratory research on integrating engineering information,design,construction,and operation of lightweight glubam structure on BIM platform was conducted.Some suggestions on the development of BIM systems based on modern internet and the management of lightweight glubam structures were proposed.